THIS IS A RUSH TRANSCRIPT. THIS COPY MAY NOT BE IN ITS FINAL FORM AND MAY BE UPDATED.

[18:00:05]

WOLF BLITZER, CNN ANCHOR: Is it escalating its war on the news media?

Still campaigning. President Trump takes a victory lap at a conservative conference, touting his hard-line agenda. Are Republicans united behind him?

And deadly development. Police now say the half-brother of North Korea's Kim Jong-un was killed with a banned chemical nerve agent. Who was behind the murder?

We want to welcome our viewers in the United States and around the world. I'm Wolf Blitzer. You're in the THE SITUATION ROOM.

We're following new developments in our exclusive reporting. Tonight, the White House says it did nothing wrong by asking the FBI to deny reports of communications between President Trump's campaign aides and Russians known to U.S. intelligence.

The president himself didn't address the issue as he spoke to the annual conservative conference known as CPAC. Instead, he promoted his aggressive agenda and launched new attacks on the news media, saying dishonest reporters do -- quote -- "a tremendous disservice to our country."

Shortly after the president's speech, media organizations, including CNN and "The New York Times," were blocked from attending an off- camera White House briefing. The move is believed to be unprecedented in modern times and prompted some other news media organizations to boycott the press briefing.

Also tonight, police in Malaysia say one of the most deadly and fastest-acting chemical nerve agents ever developed was used to kill the half-brother of the North Korean dictator, Kim Jong-un. The agent is known as V.X. and was banned under a 1993 chemical weapons agreement.

We're covering all of that, much more this hour, with our guests, including Congressman Joaquin Castro. He's a member of the Intelligence and Foreign Relations Committees. And our correspondents and expert analysts are also standing by.

Let's begin with our exclusive reporting on communications between the Trump campaign and Russians known to U.S. intelligence.

Our chief national security correspondent, Jim Sciutto, broke the story for us yesterday.

In the midst of all the media criticism from the White House, the White House did confirm the essence of the story, that is, that it did speak to the FBI about these communications and it did ask the FBI's help in knocking down these stories describing them.

More broadly, the White House has not categorically denied the existence of communications between Trump advisers and Russians known to U.S. intelligence during the campaign, which CNN reported last week.

(BEGIN VIDEOTAPE)

SCIUTTO (voice-over): Tonight, the White House vehemently defending, asking the FBI to deny reports of communications between Trump campaign associates and Russians known to U.S. intelligence.

The administration's intense pushback follows CNN's exclusive reporting of the White House request. Senior administration official insisting it only asked for the denial after a top FBI official himself volunteered that "The New York Times"' story on those communications was inaccurate.

White House officials, who asked not to be named, today outlined their timeline of events, saying, the conversation happened on February 15, after a 7:30 a.m. meeting led by White House Chief of Staff Reince Priebus. FBI Deputy Director Andrew McCabe asked Priebus for five minutes alone after the meeting ends, this according to senior administration officials, and called the reports linking Trump campaign advisers to Russia -- quote -- "total B.S."

Priebus, the White House said, asked McCabe -- quote -- "Can we do anything about it?" and whether there is something the FBI can do to -- quote -- "set the record straight."

Later, in separate conversations, McCabe and FBI Director James Comey tells Priebus the FBI cannot comment on the reports. Priebus then asks Comey if he can cite McCabe and Comey as -- quote -- "top intelligence officials" in pushing back on the story himself in TV interviews last Sunday, which he did.

REINCE PRIEBUS, WHITE HOUSE CHIEF OF STAFF: I have talked to the top levels of the intelligence community and they have assured me that that "New York Times" story was grossly overstated and inaccurate and totally wrong.

SCIUTTO: The direct communications between the White House and the FBI were unusual because of decade-old restrictions on such contacts concerning pending investigations.

ALBERTO GONZALES, FORMER U.S. ATTORNEY GENERAL: You don't even want the appearance of political influence with respect to an investigation or prosecution. That's why the protocols are in place.

SCIUTTO: President Trump on Friday ranted against the leaks that have plagued his administration, making a case reporters should only used named sources, even as White House officials spoke to reporters asking not to be named.

DONALD TRUMP, PRESIDENT OF THE UNITED STATES: I'm against the people that make up stories and make up sources. They shouldn't be allowed to use sources unless they use somebody's name. Let their name be put out there. Let their name be put out.

[18:05:10]

(APPLAUSE)

TRUMP: A source says that Donald Trump is a horrible, horrible human being. Let them say it to my face.

SCIUTTO: Mr. Trump also criticized the FBI directly, tweeting -- quote -- "The FBI is totally unable to stop the national security leakers that have permeated our government for a long time. They can't even find the leakers within the FBI itself. Classified information is being given to media that could have a devastating effect on U.S. Find now."

(END VIDEOTAPE)

SCIUTTO: On the larger issue of communications between Trump associates and Russians known to U.S. intelligence during the campaign, you heard Reince Priebus there seem to say that there is nothing to these stories, but the fact is, the FBI is still investigating these communications, as are both the Senate and House Intelligence Committee. That investigation, Wolf, as you know, is now under way.

BLITZER: Jim Sciutto reporting for us. Jim, thank you very much.

We're also following breaking news, tension between the White House and the news media escalating tonight after Press Secretary Sean Spicer blocked CNN, "The New York Times," "The Los Angeles Times," other major news organizations from an off-camera press briefing.

Our White House correspondent Sara Murray has more.

Sara, you were kept out. You were standing in line ready to go into that briefing and they told you, you were not on the list.

It was clear that CNN and a number of other media outlets were not welcome in this briefing with the White House press secretary today. It's worth noting that sometimes the White House will do smaller briefings.

For instance, sometimes, they will invite columnists to come in for a meeting. But this was bizarre because of the way they hand-picked different news outlets. For instance, they invited every major television network except for CNN. They had newspapers in there, but they didn't allow "The New York Times" or Politico in there, but they did allow a number of news outlets that are more favorable, more conservative-leaning.

Breitbart was allowed in. One America News Network, "Washington Times" all of those were invited into this briefing with Sean Spicer that was not on camera. The other perplexing thing about this is that from the readout that we got from this briefing is it sounds like Spicer spent most of his time in there discussing this story that CNN broke about conversations between the White House chief of staff and the FBI and yet CNN wasn't allowed into that.

Now, I have asked a number of different folks in the communication shop for comment on why they chose to sort of cherry-pick these news outlets the way they did. They have not answered that question, Wolf.

BLITZER: Given you no explanation at all, no public statement explaining why CNN and these other major news organization were barred from what is usually a pretty regular event, a gaggle, so-called, off- camera briefing for the news -- for the accredited White House correspondents.

MURRAY: That's right. It's usually a pretty run-of-the-mill event. The only thing they have said is that the pool was allowed in, which allowed them to disseminate the information to everyone.

And while that is true, this is also an expanded pool where they, as I said, sort of hand-selected the other news outlets they allowed in. And again they won't answer the question of why they chose to do it this way, why they chose the specific news outlets they did to allow in and blocked out others.

BLITZER: I understand you have some more, new reporting, Sara, about some frustration now emerging in the Trump White House.

MURRAY: The other thing we are learning tonight is about the conversations between White House Reince Chief of Staff Reince Priebus and the FBI.

And what we're hearing is there is some consternation in the White House about what happened there and that this is a distraction that the president really was not looking for at this point. We know -- and this source reiterated that he has become frustrated recently with the amount of negative coverage, particularly around the staff stories, that he wants to focus on his core agenda items.

And, again, when you're facing headlines about conversations that the chief of staff had with high-ranking officials at the FBI, that is not the headline the president was hoping to see, certainly not what he was hoping to focus on today.

BLITZER: Just to be precise, there are frustrations at the White House chief of staff, Reince Priebus? Is that what you're reporting?

MURRAY: Yes, frustrations about White House Chief of Staff Reince Priebus having these conversations and the fact that this is another thing that could reflect negatively on this White House at a time when that's not the kind of headline they're looking for, Wolf.

BLITZER: That's understandable. Sara Murray, doing some good reporting for us as usual, thank you.

Let's get some more on all of this.

Democratic Congressman Joaquin Castro of Texas is joining us. He's a member of both the Intelligence and Foreign Affairs Committees.

Thanks so much, Congressman, for joining us.

REP. JOAQUIN CASTRO (D), TEXAS: Thanks for having me, Wolf.

BLITZER: Let me get your quick reaction to that report from Sara Murray on the White House blocking CNN and other major news organizations from what has always been a routine press briefing. They call it an off-camera gaggle. What's your reaction when you heard that?

[18:10:02]

CASTRO: Well, it's bad news.

Watching everything that's going on, you can't help but think that Donald Trump is trying as hard as he can to follow in Richard Nixon's footsteps, allegations of a cover-up, a very hostile environment with the press.

And the worst it's gotten for them in terms of press coverage, the more they're trying to control who can write the stories about the administration. And I think that's what you have seen today.

BLITZER: Let's talk about the other top story, Congressman, revelations that the White House asked the FBI to knock down reports of contacts between Trump aides and Russian officials during the campaign.

The White House is insisting they didn't do anything wrong. You sit on the Intelligence Committee, which has already been investigating links between Russia and President Trump's fired national security adviser, Michael Flynn. Would you like to see your committee also dig into these new revelations?

CASTRO: Right.

Yes, absolutely, this should be part of it. And it seems like it's one thing after another that the Senate and House committees are going to have to investigate, everything from General Flynn's contacts with the Russians to other campaign advisers who may have had contacts and relationships with the Russians, and now perhaps the White House possibly trying to strong-arm the FBI into -- you know, into shaping the coverage, the news coverage about the story.

And it's hard to give the administration the benefit of the doubt because they have been so hostile not only to the press, but also to the intelligence agencies, to the CIA before, and then today Donald Trump unloading on the FBI.

So, you know, that's what makes me think that perhaps there was some kind of strong-arming going on.

BLITZER: Are you confident that your committee or, in fact, any other committee in the House or the Senate can conduct a thorough investigation? I ask the question because your colleague on the committee Jim Himes, he told CNN that he'd like to see a 9/11-style investigation looking into this because that would remove some of the political pressures that come from being a member of Congress.

CASTRO: Jim and I agree on that.

We both support an independent and bipartisan commission that can have a full and fair investigation into the whole Russia issue. Now, remember, Democrats, of course, are in the minority in both chambers. So, we can't create that kind of commission. Republicans would have to do that.

But in lieu of that, then the House and Senate investigations need to be full and fair. And also, Wolf, I would say this. They need to proceed at a brisk pace, which has not happened so far.

BLITZER: You tweeted this today. And I will put it up on the screen. "The White House shouldn't interfere with an FBI investigation or instruct a cover-up. If report true, need major staff shakeup."

What are you suggesting as far as the president and his staff at the White House are concerned?

CASTRO: Well, this should be part of the investigation.

And if the chief of staff tried to strong-arm the FBI or recommended some course of action for them to take, knowing full well that much of this stuff is under investigation currently, then whoever gave that order needs to go.

BLITZER: What about potential impropriety on the part of the FBI? The White House says the FBI deputy director, Andrew McCabe, originally reached out to them to talk about the report in "The New York Times" regarding contacts with Russia.

If that's true, should McCabe face disciplinary action as well?

CASTRO: Sure.

That's a decision for Director Comey. But, look, anybody who broke the rules should pay a price.

BLITZER: The attorney general, Jeff Sessions, as you know, was a very strong supporter of the president during the campaign. He was the first U.S. senator to endorse Mr. Trump.

Given his political connections to the president, do you believe he should recuse himself from these investigations?

CASTRO: I do think he should recuse himself, both for his own integrity and credibility, but also because, as you mentioned, he's been very close to the president. And he's not in the best position to be a fair and impartial person in this case.

BLITZER: We're going to take a quick break, Congressman. But there is much more to discuss.

I will ask you to stay with us. We will resume this right after this break.

(COMMERCIAL BREAK)

[18:18:40]

BLITZER: We're back with Democratic Congressman Joaquin Castro, a member of the Intelligence and Foreign Affairs Committee.

We want to talk to him about President Trump doubling down on his most controversial position and policies in a campaign-style speech over at the annual conservative conference known as CPAC.

We're going to get back to you, Congressman, in a moment.

But our congressional correspondent, Phil Mattingly, is on the scene for us at that CPAC conference.

Phil, this was a victory lap for the president.

PHIL MATTINGLY, CNN CORRESPONDENT: Yes, no question about it.

Think about it this way, Wolf. Just one year ago, at the same event, many of the attendees were cool at best, completely opposed at worst, to then-candidate Trump. Now he's President Trump and his agenda is something many of them support wholeheartedly.

(BEGIN VIDEOTAPE)

TRUMP: The era of empty talk is over. It's over.

MATTINGLY (voice-over): Tonight, President Trump, the man who surprised the Republican Party and its conservative activists, laying out his hard-line agenda to a movement that has become his own.

TRUMP: As we speak today, immigration officers are finding the gang members, the drug dealers, and the criminal aliens, and throwing them the hell out of our country.

(CHEERING AND APPLAUSE)

TRUMP: And we will not let them back in. They're not coming back in, folks. [18:20:05]

MATTINGLY: Pledging to send Congress a request for a major boost in funding for the U.S. military.

TRUMP: We're also putting in a massive budget request for our beloved military.

(CHEERING AND APPLAUSE)

TRUMP: And we will be substantially upgrading all of our military, all of our military, offensive, defensive, everything, bigger and better and stronger than ever before.

MATTINGLY: And again leveling an attack on an American ally, this time Paris, France, citing an unknown friend named Jim, who told him:

TRUMP: Paris? I don't go there anymore. Paris is not longer Paris.

MATTINGLY: Which quickly garnered this Twitter response from the city's mayor, a pick from the Eiffel Tower with Mickey and Minnie Mouse.

Trump's campaign-style speech even targeted his former rival Hillary Clinton for once calling Trump supporters deplorables. Trump tossing red meat, bold promises and, of course, no shortage of attacks directed at the media.

TRUMP: A few days ago, I called the fake news the enemy of the people, and they are. They are the enemy of the people.

MATTINGLY: Mocking the First Amendment.

TRUMP: You know, they always bring up the First Amendment. And I love the First Amendment. Nobody loves it better than me.

MATTINGLY: But it was his sharply consistent pledge to stick to the very agenda he laid out during the campaign that resonated with the crowd.

TRUMP: So, let me state this as clearly as I can. We are going to keep radical Islamic terrorists the hell out of our country.

(CHEERING AND APPLAUSE)

MATTINGLY: All as Trump promised new anti-terrorism actions in the days ahead.

TRUMP: In a matter of days, we will be taking brand-new action to protect our people and keep America safe. You will see the action.

(END VIDEOTAPE)

MATTINGLY: Wolf, the president's nearly hour-long speech really was a remarkable moment, if you look over the past couple of years, not just last year, when attendees weren't so excited about his candidacy, but all the way back to 2011.

It was his first speech to the CPAC conference. The president kind of went through that today through his remarks, making clear that it was after that speech that he realized, hey, this politician thing might not be so bad.

The evolution of candidate Trump to President Trump really starting here at CPAC. The crowd responding to that and the president's agenda here today in Maryland -- Wolf.

BLITZER: He seem to be very well-received over there.

All right, Phil, thank you, Phil Mattingly reporting.

Let's get back to Congressman Joaquin Castro, who is joining us.

Congressman, we learned also today Customs and Border Protection officials will soon begin collecting proposals to design and build what they are calling a prototype wall structure or structures near the southern border with Mexico.

And President Trump said at CPAC today that the border wall is way ahead of schedule. You represent a district in a border state in Texas. What's your reaction to that news?

CASTRO: Well, I have said for quite a while, as many others have also, that spending tens of billions of dollars on a border wall is a bad idea.

There are so many ways that we could spend that money. And I also think that wall is going to be ineffective.

BLITZER: Yesterday, the president described recent deportations as a military operation. That's the way he phrased it. The White House later clarified that he was using that phrase as an adjective to describe the precision of those deportations.

You have expressed concerns that the administration is planning mass deportations. Are you concerned that the president might try to use some sort of military force to enact his policy?

CASTRO: Sure.

At this point, after what we have seen, I wouldn't rule anything out. You think about what just happened the other day, where CBP agents were checking the documents, the papers of everybody who was deplaning from a domestic flight from San Francisco to New York.

ICE agents have gone over to a domestic violence court and removed a woman from the court who was seeking a protective order. There was a woman who had a brain tumor who was a few days away from having surgery to have that removed or dealt with, and she's been in a detention center, from what I understand.

We have heard other stories of Americans, American citizens and legal residents getting caught up in this dragnet. So, to be honest with you, at this point, I really wouldn't put anything past him.

BLITZER: Well, let me give our viewers some background on what you're talking about, that one story, that developing story. We're tracking it as well.

[18:25:00]

Passengers on a domestic flight from San Francisco to New York were told to present identifying documents to agents from Customs and Border Protection when they touched down. The agency says they were searching for an undocumented official who had been ordered removed by an immigration judge.

This is highly unusual because those agents are typically limited to checking international arrivals. Do you believe this amounted to an illegal checkpoint of passengers on that domestic flight?

CASTRO: Quite possibly, Wolf.

And, at that meeting with ICE several days ago, I asked a direct question, whether there would be any random citizenship or document checks. And their answer was a clear no.

That seems to violate basically what they promised to us, as members of Congress in that room, and what they have said to the American people. So, are they saying that any time they're looking for an undocumented person, that 300 people or 400 people are going to be subjected to being asked for their citizenship documents?

If so, then there are going to be millions of Americans from every walk of life and background who are going to be caught up in this large dragnet.

BLITZER: Congressman, the homeland security secretary, John Kelly, and the secretary of state, Rex Tillerson, they were in Mexico yesterday. They tried to reassure the Mexican government that President Trump's deportation policies will be carried out legally and humanely.

But many Mexican officials did not seem convinced. What do you make of the rocky start to this U.S. relationship with Mexico?

CASTRO: Well, remember, Mexico is one of our three largest trading partners. They have been a nation with whom we have been great friends over the years.

And so the president has shown a real hostility towards Mexico. And I said early on, look, if they insist, if Donald Trump insists on making Mexico pay for a wall, if he does that by taking away foreign aid, for example, then I'm sure that China, Xi Jinping is more than happy to step in and offer them whatever Donald Trump takes away.

So, to me, in terms of the geopolitics, it's creating a wide-open door for a competitor nation in China to go in there and really get a foothold in Mexico and Latin America.

(CROSSTALK)

BLITZER: Yes, I was going to say, I noticed when the president spoke at CPAC today, he promised to build that wall, but he avoided saying Mexico was going to pay for it. Go ahead.

CASTRO: And then also, Wolf, I know that Rex Tillerson, who is a distinguished man, who has had a distinguished career, went down there and came off in a friendly tone and seemed to give some reassurances, but the fact is, at this point, you know, our allies don't know whose word to trust.

The White House, depending on who you ask, gives three or four or five different versions of an answer on controversial issues. So, unfortunately, it's gotten to a point where our diplomats can go to a country and offer assurances and really those countries don't know whether their word can be taken or not.

BLITZER: Congressman Joaquin Castro, thanks so much for joining us.

CASTRO: Thank you.

BLITZER: Just ahead, we will have more on the White House pushback on asking the FBI to deny reports about the Trump campaign and Russia.

Plus, we have details on the chemical nerve agent used to kill the half-brother of North Korea's Kim Jong-un.

(COMMERCIAL BREAK)

[18:38:07] BLITZER: More now on our exclusive reporting. Tonight, the White House says it did nothing wrong by asking the FBI to deny reports of communications between President Trump's campaign and Russians known to U.S. intelligence.

Let's bring in our analysts, and Phil Mudd, I want to start with you. You used to work at the CIA, you were detailed for, what, four or five years to the FBI. You're familiar with these areas. This is what the President tweeted today. "The FBI is totally unable to stop the national security leakers that have permeated our government for a long time. They can't even find the leakers within the FBI itself. Classified information is being given to media that could have a devastating effect on U.S. Find now."

He's blaming the FBI for this investigation. And in the process, he seems to be confirming CNN's exclusive reporting.

PHILIP MUDD, FORMER CIA COUNTERTERRORISM OFFICIAL: He is confirming the reporting and he's doing something more remarkable, Wolf. And that is, in the midst of his comments, his tweets about the FBI, how many people including the tweeter in chief from the Oval Office are talking about what happened several months ago, that was Russian involvement in U.S. elections. We have a bait and switch here for the American people.

The media brought us coverage of Vietnam, coverage of Watergate, coverage of the Afghan and Iraq wars and now coverage of Russian involvement in American elections, and what does the President do? He denigrates one of the most respected institutions at America, that is the FBI.

If you're the FBI, you got to have a couple of comments here watching this show over the past few days. Number one, I better be darn careful anytime I touch a politician because they're going to throw me under the bus despite the fact that it's my responsibility to prosecute federal law.

Number one, if I'm the FBI at least privately not publicly, I'm going to say you want us to investigate the Russians, you want to attack us, be careful. We're coming at you.

Now, I would redouble this investigation because the President is like a bullfighter holding out a red cape to the American people. Focus on the leaks he's saying, don't focus on the Russians. The bureau has got to be ticked off.

[18:35:06] BLITZER: Well, some officials seem to be ready to throw Andy McCabe, the deputy director of the FBI, Phil, under the bus. You know him. Tell us about him.

MUDD: Look, I've worked with Andy for years. For the American people who want to denigrate their public service, Andy McCabe has one conversation with a politician in the White House, who's doesn't know how to deal with national security information, an individual, Andy, who's got decades of experience in government. Somebody -- I would not only trust an investigation, too. I'd trust my 10 nieces and nephews, too. And the President decides on the basis of that, he's going to throw him under the bus.

Let me tell you something, this guy is a terrific officer. This says a lot more about the White House diverting attention than it does about the FBI doing what American pay him to do. What the heck did the Russians do to obstruct an American election? That's the story, Wolf, not the President's tweet.

Evan Perez, you've been doing a lot more reporting on this. What else are you hearing?

EVAN PEREZ, CNN JUSTICE CORRESPONDENT: Wolf, part of the problem today is that the White House is trying to, you know, give us shiny objects to focus on. Look --

BLITZER: Explain what you mean by that.

PEREZ: The problem is, you know, the blocking of the reporters and also, as Phil pointing out, the -- you know, trying to throw Andy McCabe under the bus for what they say was initiating the conversation with Reince Priebus.

The issue here is that even after that conversation, the FBI -- I'm sorry, the White House kept calling the FBI trying to pressure them essentially to try to refute these stories. And the reason why the FBI can't do that, this is an ongoing investigation. And really in the end, the "New York Times" may have had a couple of things wrong in their story. But the essence of it is accurate, which is, that there were contacts between people associated with the Trump campaign and people in Russia, people who are known to U.S. intelligence.

And this was happening at a time that the Russians were trying to interfere with the U.S. elections. That's an incredibly, incredibly serious story. And I know that the White House would like to talk about other things but that's what the FBI is focused on investigating and I think that's what, you know, we all should keep an eye on.

BLITZER: And to smear the FBI, as Phil says, that's really, really awful. And then earlier, remember, he smeared the intelligence community, the CIA, when he made that comparison to Nazi Germany. So, all of this potentially could have --

PEREZ: These people are professionals. They're going to keep doing their job. I mean -- but it's not right for the President to be attacking them, you know, for doing what they do.

BLITZER: There was another development. One of those shiny objects that came up today. Brianna, you've been covering it as well, when they blocked major news organizations like CNN, the "New York Times," POLITICO, the "Los Angeles Times" from attending a routine press briefing, off-camera briefing. See some of the organizations. But listen to what Sean Spicer said back in December during the transition.

(BEGIN VIDEO CLIP)

SEAN SPICER, REPUBLICAN NATIONAL COMMITTEE COMMUNICATIONS DIRECTOR: And I think we have a respect for the press when it comes to the government, that that is something that you can't ban an entity from. You know, conservative, liberal, or otherwise, I think that's what makes a democracy versus a dictatorship.

(END VIDEO CLIP)

BLITZER: You've been doing some reporting on all of this. What are you learning?

BRIANNA KEILAR, CNN SENIOR WASHINGTON CORRESPONDENT: Well, I think part of what you're seeing there, Sean Spicer back in December was him trying to comfort people that, don't worry too much, we are going to be a White House that is the way other white houses, George W. Bush, the way they have related to the press.

I don't think it's particularly surprising, though, just being familiar, I think, certainly with what we've heard from the President and also what we know about Sean Spicer from the past. You know, I was talking to a former Republican colleague of his, and back when he was at the RNC, you know, he talked about internally banning outlets.

He talked about sending out memos that would call out what he felt was false reporting and we also know that Mashable recently reported out -- they just found Sean Spicer that a URL was registered to him, RateTheReporter.com. So I mean, these are a number of data points that tell you what we're seeing is in line certainly with Sean Spicer's philosophy on this.

But again, you also pointed out, it's part of it, that it's a shiny thing. It is a distraction. The White House doesn't want to be talking about this story, that Evan has very well reported out.

BLITZER: They certainly -- the reporting is excellent reporting, Evan. And you and your colleagues have done a great job.

It's one thing to ban a news organization during a campaign, as the Trump campaign did occasionally, "Washington Post" among other news organization. That's a private organization, they can do what they want. But it's another thing when you're -- the White House, the U.S. government and you're telling major news organizations to routine briefings, you're not welcome.

REBECCA BERG, NATIONAL POLITICAL REPORTER, REAL CLEAR POLITICS: Exactly. This wasn't, you know, an informal sort of gaggle. It was a little different than the daily briefing you would usually see at the White House. It wasn't televised. But it was still on the official schedule. And reporters have an expectation that they should be allowed into that briefing. Any credentialed press at the White House is allowed into White House briefings.

[18:40:03] This is a major exception, as Dean Baquet, the editor of the "New York Times" said in his statement, this is something that has not happened at the White House before. And the White House should be taking this seriously, we as reporters should be taking this seriously. It certainly sends a strong message in terms of how the White House is approaching the press.

And this comes at a time where you're hearing very worrisome rhetoric from the President himself, calling the press the enemy of the American people. Trying to erode the President's credibility, those things matter coming from the President.

BLITZER: Yes, I spent seven years as a White House correspondent, never happened on my watch.

But Phil, let me play another clip. The President is starting the day at that CPAC Conference speaking about the first amendment.

(BEGIN VIDEO CLIP)

TRUMP: They say that we can't criticize their dishonest coverage because of the first amendment. You know, they always bring up the first amendment. And I love the first amendment. Nobody loves it better than me. Nobody.

(END VIDEO CLIP)

BLITZER: Now, he's been widely criticized for seemingly mocking the first amendment. I'm anxious, Phil, to get your thoughts.

MUDD: Look, he's attacked the judiciary during his presidency for their decisions on immigration, he's attacked the Congress repeatedly. Now, he's attacked the media which he's done before. This is a man who doesn't respect balance of power which is a

fundamental principle and government, and checks and balances.

Let me tell you something, the media, in my experience at the FBI and CIA, I spent dozens of interviews with them is difficult to deal with. Because every time we made a mistake, every time we misspent money, every time we had an operation, we went -- that went south. Every time we had an operation that the American people needed to know about. For example, in my experience, CIA blocks sites secret facilities overseas, the media was on us.

For everybody who cheered the President, let me ask you one question, if you don't want the media to operate, remember Vietnam, remember Watergate, remember Iraq, remember Syria. Who do you want to investigate the activities of the American government?

And if your answer is the Congress, look at the approval rating for the Congress among the American people because that's lower than the approval rating for the media. Be careful what you wish for. It's a president who doesn't respect checks and balances.

BLITZER: Good point. All right, standby, everybody. Standby. There's much more coming up. Hillary Clinton tells Democrats to keep fighting and keep the faith. But does she have an answer for the troubled state of the Democratic Party?

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[18:47:01] BLITZER: President Trump today renewed his attacks on the news media as he addressed the annual conservative conference CPAC, calling some news organizations, quote, "the enemy of the people," and saying dishonesty reporters do, quote, "a tremendous disservice to our country."

You know, Evan, at some point, he seemed to be hitting "The Washington Post" for using nine anonymous sources to report, you remember this, that the former National Security Adviser Michael Flynn had ties to Russia. But that story eventually led to Flynn's departure.

PEREZ: That story was completely accurate, Wolf, and the problem here is that the irony of all of this is that in response to trying to kill the "New York Times" and CNN's reporting about these contacts between his people associated with his campaign and Russians, he was -- his White House was pushing the FBI to anonymously talk to reporters, to knock down the story.

His White House has used anonymous sourcing including today, including today. This morning, they brought in reporters and had two senior administration officials speak to reporters to try to help massage their message and in the end confirmed the story we reported last night.

So, the irony here is that they use anonymous sourcing all the time, including Donald Trump obviously back in his real estate days. KEILAR: John Barron.

PEREZ: So, he's familiar with it.

KEILAR: Pretending to be someone else.

Anonymous sourcing is not bad. That's the other thing you have to understand. Watergate, an anonymous source.

PEREZ: Right.

KEILAR: Having anonymous sources and you have to do with some care to make sure that you're corroborating what they're saying, but this is something that is a discussion certainly. It's not just something, it's not like a reporter doesn't tell their editor. There is a discussion about this, there is a close hold.

And when you have an anonymous source, it allows them to be comfortable, telling you what is going on, because what you get on the record is just white washed so often.

BLITZER: Because, you know, the president said to reporters, don't report anything unless you mention the name of the individual who said that to you. He said that, within a few minutes after, there was this 45-minute background briefing at the White House and reporters were told, you can't mention the names of the individuals telling you this information.

BERG: Right. I mean, it's completely inconsistent. Of course, that is the platonic ideal of any journalism, that we're able to put out there on the record who is saying exactly what, who is giving us this information.

But, Brianna is exactly right. This is for the most important stories that is happening inside this administration, people don't want to risk losing their jobs, they don't want to lose their jobs. Donald Trump has said that he will go after anyone who is leaking to the press. They want to be able to talk candidly about what is happening in this administration.

And the fact that Donald Trump is coming out and saying that anything with anonymous sourcing is just not true, it's not reliable, this is a strategy on his part to try to discredit the media, discredit stories that he doesn't like. Make no mistake, this is intentional, it is an intentional --

BLITZER: I'm anxious to get Phil Mudd's thoughts.

Go ahead, Phil.

MUDD: Let me be clear, I've served as an anonymous source on the other side of this. If you don't like anonymous sources, let me reflect the conversation that just happened.

[18:50:03] If I speak as Phillip Mudd when I was back at the FBI or CIA, the chance that the American people will get the real story is far diminished than if the press office comes to me and says, Mr. Mudd, will you speak to CNN, "The Washington Post", "The New York Times" and we'll allow you to speak on what's called background, that is they can use the information, they can quote you as anonymous source, but they can't use your name.

If you want the story, Wolf, stick with anonymous sources. I was one of them.

BLITZER: You know, Brianna, I want to play quickly a little clip. This is Hillary Clinton speaking about her party and the Democrats.

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HILLARY CLINTON, FORMER PRESIDENTIAL CANDIDATE: Stay focused on the elections we must win this year and next. Let resistance plus persistence equal progress for our party and our country.

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BLITZER: Tomorrow, they're going to be electing a new chair of the Democratic Party. But this party right now pretty divided.

KEILAR: That's right. And we saw that play out in the election, and I think it's interesting that you see Hillary Clinton in this video, because what Democrats really need as they're facing divisions, and just beyond the DNC chair, they need a new face.

And we see Hillary Clinton is a face of the past for the Democrats, they need a face for the future, someone who can unify the party. We saw in 2008, even as we saw a pretty divided Democratic voters, they still in the end were able to unite behind someone.

BLITZER: All right. Everybody, stand by.

There's much more coming up, including North Korea. Did North Korea use the deadliest of all nerve agents to kill the half brother of Kim Jong-Nam? We have stunning new details.

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[18:56:03] BLITZER: A stunning new development tonight in the death of the half brother of the North Korean dictator Kim Jong-un. Officials in Malaysia where he died now say he was killed with a chemical nerve agent known as VX.

Our Pentagon correspondent has been working her sources.

Barbara, this is one of the most toxic and fast acting nerve agents in chemical warfare.

BARBARA STARR, CNN PENTAGON CORRESPONDENT: Wolf, VX is a kill agent pure and simple. How the attackers got it inside a busy commercial airport is just one of the many unanswered questions tonight.

(BEGIN VIDEOTAPE) STARR (voice-over): It's one of the deadliest chemical agents in the world, VX. The Malaysian government says it was used to assassinate Kim Jong-nam, the estranged half brother of Kim Jong-un, and local authorities believe North Korea may have been behind the murder.

A U.S. official tells CNN, quote, "It certainly appears" North Korea attacked using a weapon of mass destruction agent when two women approached Kim Jong-nam in the airport in Kuala Lumpur and attacked with a substance they put on his face.

STEVE HALL, FORMER CIA OFFICER: Given the fact that VX is not only one of the most lethal agents out there, nerve agents out there, it's also something you just can't make in your basement. It is a step across a line.

STARR: Intelligence services worldwide are watching closely.

HALL: Exact methodology as to how it got into a controlled area of an international airport, I think would be the subject of continued intelligence collection.

JIM WALSH, M.I.T.: They had an active storage site with VX that they could have confidence in, they would not have to transport very much of it and no one would know what it was without opening it unfortunately and dying from it.

STARR: Malaysia has already asked Interpol to put out an alert for four missing suspects. But the fear is they are already back in Pyongyang.

The Malaysian police report details that after he died, Kim Jong-nam's eyes and face were swabbed by investigators. They found VX nerve agent. That has not yet been confirmed independently.

The Organization for the Prohibition of Chemical Weapons which represents 192 nations issued a statement saying, "Any use of chemical weapons is deeply disturbing", and offering technical assistance to the Malaysians.

KHALID ABU BAKAR, MALAYSIAN INSPECTOR, GENERAL OF POLICE: I'm only saying that the cause of his death is by that chemical. The rest will be subject of our investigation.

STARR: Security was increased at the morgue where Kim Jong-nam's body is being held after an attempted break in.

VX is an internationally banned chemical weapon that can kill in minutes. It causes convulsions, paralysis, loss of consciousness and death due to respiratory failure.

While North Korea has not acknowledged it has chemical weapons, South Korea estimates the regime has a stockpile of up to 5,000 metric tons. The U.S. says it's always prepared for North Korean attacks, and 28,000 U.S. troops in South Korea regularly practice operating in a chemical assault.

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STARR: And the North Koreans have continued to push back, saying they were not responsible for this and saying, if those two women had a lethal toxic agent on their hands at the airport, how could they have survived? Wolf?

BLITZER: And if the authorities there had atropine, he might have survived, right?

STARR: Well, it probably would have depended on the level of the dose, I think, and how quickly, in fact, they could have gotten to him. But nobody really could have fathomed that this was about to happen.